97891 has 4 divisors (see below), whose sum is σ = 99792. Its totient is φ = 95992.

The previous prime is 97883. The next prime is 97919. The reversal of 97891 is 19879.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19879 = 103 ⋅193.

It is a cyclic number.

It is not a de Polignac number, because 97891 - 2³ = 97883 is a prime.

It is a Duffinian number.

97891 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (97841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 871 + ... + 976.

It is an arithmetic number, because the mean of its divisors is an integer number (24948).

2⁹⁷⁸⁹¹ is an apocalyptic number.

97891 is a deficient number, since it is larger than the sum of its proper divisors (1901).

97891 is a wasteful number, since it uses less digits than its factorization.

97891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1900.

The product of its digits is 4536, while the sum is 34.

The square root of 97891 is about 312.8753745503. The cubic root of 97891 is about 46.0872634653.

The spelling of 97891 in words is "ninety-seven thousand, eight hundred ninety-one".